Teeth are essential organs for animal survival and of obvious clinical and/or cosmetic importance. There are many instances where tooth replacement is desirable and current treatments are restricted to artificial prostheses or implants.
Tooth primordia explants can be cultured in vitro allowing a variety of manipulation studies including introduction of genes and/or proteins and tissue recombinations. Manipulated primordia can be transferred to renal capsules of adult animals (such as mice) to produce conditions for development of adult teeth. However, these culture techniques require frequent animal sacrifice. This is one of the problems associated with the prior art.
Prior art approaches to the production of tooth primordia relied on in vitro tissue recombination. Two different tissue types were independently dissected from the animal embryo, and these were recombined in the laboratory. Signals from one may then induce formation of tooth primordia in the other. This is a labour intensive process carried out by highly trained workers involving a great deal of surgical skill.
According to the prior art, the tissue requirements for progression of tooth development change early in development. For initiation, it is thought that oral epithelium is essential and can form teeth when recombined with any mesenchymal cells, as long as they are derived from the neural crest. Thus, according to the prior art, neural crest derived cells are essential for the formation of tooth progenitor cells.
The present invention seeks to overcome at least some of the problems associated with the prior art.